Seal arrangement for floating roof



Oct. 27, 1964 R. c. ULM 3,154,213

SEAL. ARRANGEMENT FOR FLOATING ROOF Filed June 18, 1959 s Shets-Sheet 1mumm /1111111111 I Oct. 27, 1964 R. c. ULM

SEAL ARRANGEMENT FOR FLOATING ROOF 3 Sheets-Sheet 2 Filed June 18, 19593% m 5 f: e ?jt f M n n 1 1 w 5 4 H :umw: U wfi; 5 2 w m D E; d 1 mm i eL 1 4 J m i 0 j i 1 f i 6 \l/ 7 w o m 1 M J 1 q R. C. ULM

SEAL ARRANGEMENT FOR FLOATING ROOF Oct. 27, 1964 3 Sheets-Sheet 3 FiledJune 18, 1959 IN VEN TOR.

United States Patent 3,154,213 SEAL ARRAWGEMENT FDR FLGATING RGQF ReignC. Ulin, Schererville, Ind, assignor to Union Tank Car Company, Chicago,Ill, a corporation of New Jersey Filed June 18, 1959, 521'. No. 821,2477 Claims. (Cl. 22tl--26) The invention relates to sealed storage tanksof the floating roof variety, and particularly to a novel pressure sealarrangement therefor.

It is a primary object of the invention to provide a unique flexibletube arrangement to seal the annular space between a sealed storage tankshell and the upstanding rim of a roof therein.

It is a further object of the invention to provide in an arrangement ofthe type described, a unique mounting structure which accommodatesimproved floating roof operation under all roof conditions.

These and other objects of the invention will become apparent in thecourse of the following description, and from an examination of theassociated drawings, wherein:

FIGURE 1 is a plan fragmentary view of a floating roof storage tankincorporating the invention,

FIGURE 2 is a sectional view taken along lines 22 of FIGURE 1,

FIGURE 3 is an enlarged, detailed sectional view of certain structureshown in FIGURE 2,

FIGURE 4 is a detailed view of certain of the connection means employed,

FIGURE 5 is a sectional view similar to FIGURE 2 of a modifiedembodiment of the invention,

FIGURE 6 is a detailed View of certain connection means employed in theembodiment of FIGURE 5,

FIGURE 7 is a side elevational sectional view of the anti-turningarrangement employed, 7

FIGURE 8 is a sectional view taken along lines 88 of FIGURE 7, and

FIGURE 9 is a sectional view similar to FIGURE 6 of a slightly modifiedarrangement.

Describing the invention in detail, and directing attention first toFIGURE 1, it will be understood that the numeral 2 indicates a steelshell of the cylindrical steel storage tank. The numeral 4 designates aconventional floating roof normally disposed in the shell and arrangedto float on product stored therein. The roof 4 is provided with anannular peripheral rim 6 which upstands from the edge thereof anddefines, with the shell plate 2, an annular space surrounding the roof4, such space being denoted S in the drawing.

To provide a seal for the annular space 8, the invention prescribes aplurality of horizontally aligned, elongated, hollow, closed-endflexible tubes 16, 10 which are arranged within the space 8 intermediatethe shell plate 2 and the rim 4. Considering FIGURE 2 specifically, itwill be noted that the tube 10 has provided thereon a continuous lip 12adjacent the upper portion thereof. The lip 12 may be arranged tooverlay a flange 14 which forms the top of the rim 6. To attach the lip12 to the flange 14, elongated clamping bars 16 are provided which arebolted to the flange 14. Thus, the upper portion of the sealing tube 10is securely fastened to the upper edge of the rim 6.

Turning to FIGURE 1, it will be apparent that adjacent abutting ends ofeach tube 10 a cylindrical fabric 20 is provided to telescopicallyreceive said adjacent ends. To provide mechanical connection between thetubes 14), the fabric 20 may be secured to the received adjacent ends inany suitable manner, as by cementing or vulcanizing. In this manner, aunitary seal is provided which extends around the entire periphery ofthe roof. Thus, the

, action of the wind or the like thereon.

3,154,213 Patented Oct. 27, 1964 seal illustrated is made up of aplurality of individual tubes 19 which must be individually inflated, ashereinafter explained. However, if desired, a unitary tube may beprovided having a common chamber around the entire roof, as hereinafterdiscussed.

To accommodate tube inflation, each tube 10 is provided with suitableinflating means 22 which may be a conventional valve or the like. Toprovide for eflective sealing, each tube 10 is inflated to a commonlevel above atmospheric pressure, whereby it will be brought intopressured engagement with the inner surface of the shell plate 2 and theouter surface of the rim 6. In this manner, an effective seal isprovided for the space 8.

Those familiar wi h the art will understand that the roof 4 will, ofcourse, rise and fall within the tank shell 2 in response to a change inliquid level therein. During upward movement of the roof, the connectionto the upper edge of the rim at 12 and 14 will be able to maintain thesealing tube 10 in proper physical disposition within the space 8.However, because of the pressure provided within each tube 10,frictional contact between the outer surface of the tube 119 and theinner surface of the shell plate 2 upon downward movement of the roofcreates a considerable drag upon each tube section. T o avoid the tuberolling out of the space 8 and upwardly upon downward movement of theroof, a one-way driving connection indicated generally at 24 isprovided. The location and manner of providing a drive connection 24 isof particular importance in the effective operation of the sealarrangement disclosed. Specifically, the one-way drive connection 24comprises an upwardly facing hook member 26 which can be seen in FIGURE4. As disclosed in FIGURE 3, the hook member 25 is connected to aflexible mounting member 28, which may be of any suitable fabric, andoverlies the base plate 39 of the hook member 26 and extends above andbelow same, as is shown in FIGURE 3. The fabric mounting member 28 maybe provided with an aperture to allow the upwardly facing hook portionto extend therethrough. The fabric mounting member 23 is then secured tothe pressure seal tube 10 in any convenient manner, such as by cementingor vulcanizing.

Those skilled in the art will understand that the roof 4 in arrangementsor" the type here under consideration frequently are biased out of acentral location in the shell by With this in mind, the particularlocation of the drive arrangement 24 accommodates considerable side orlateral flexibility in each tube 10. This will cause the tubes to expandconsiderably when the space 8 increases. Further, the one-way driveconnection 24 is such that will easily maintain each section of the tubeIt in proper location in the space 8 during downward roof movement. Onthe rim 6, a continuous angle 31 is mounted so that the outer flangethereof overlies the upwardly facing hook portion 26. Thus, thoughcontact will be maintained, pressured contact between the hook 26 andangle 31 will only occur on downward roof movement. The particularhook-like arrangements 26 may be intermittently located on the tubes 16as, for example, on twenty-four inch centers. The con tinuous angles 31will respectively register with all of the upwardly facing hook-likeportions 26 regardless of any lateral shift of the tubes on the rim. Itwill also be understood that the tube 10, being made up of individualsegments, will provide an added pressure diflerential on opposed sidesof the roof to aid in bringing the roof to a central position in thetank.

Attention is now directed to FIGURES 7 and 8 which illustrate ananti-roof turning arrangement that may be employed. Specifically, theanti-roof turning arrangement comprises a bar 32 fixedly secured to theinside of the shell 2. A shoe or shoe member 34 having an elongatedaperture therein 36, which is arranged to complementally straddle thebar 32, preferably extends from a point at or near the top of the tube10 to a point at or near the bottom of same, as is illustrated in FIGURE7. An upper strap, preferably of flexible material such as leather orfabric, is connected at its opposite ends to the shoe member 36 and tothe upper edge of the rim 12, and is indicated at 40. A second strap 42,of similar material, has its opposed ends connected to the lower end ofthe shoe 36 and to the floating roof 4. The pressured flexible bagintimately surrounds and is contoured to the shoe 36 in the areas ofengagement therebetween. This is best seen in FIGURE 8. The frictionaleffect between the contacting bag 10 and shoe 34, together with thepositioning effect of the straps 40 and 42, maintains an intimaterelationship between the shoe and the bag, and additionally prevents theroof 4 from rotary movement within the shell 2.

Consideration now will be given to FIGURE 9, Which illustrates aslightly modified tube connection arrangement. Again, it will be notedthat the rim plate 6 is provided with a downwardly extended bar angle31. A section of the flexible tube 10 immediately below the angle 31 isarranged to wrap around and embrace a flexible cord or cable 50 as at52. A spring-like flexible clip 54 demountably but securely positionsitself around the tube portion 52, and has an upwardly extending element56 received in the pocket created by the bar angle 31. Of course, aplurality of clips 54 may be provided around the entire periphery of theseal, and the cable 50 may be continuous therearound or sectionalized toaccommodate clip mounting. The clip 54 thus described functions tomaintain the tube seal 10 in proper position in a manner similar to thatearlier described.

Attention is now directed to FIGURES and 6, which illustrate a slightlymodified arrangement of the invention herein considered. The tube seal100 here shown again is continuously distributed around the entireperiphery of the roof 4. However, the tube 100 is not made up ofindividual segments, but rather presents a common chamher 102 around theentire tank shell. With a continuous chamber 102, a single valve orpressurizing point 104 may be provided. Illustrated in the figure is aflexible hose connection 106 communicating with the valve 104 which, inturn, is operatively connected to a coupling arrangement 108 which hasin series therein a closable valve 110. A pressure gauge 112 providesfor visual determination of the pressure level within the chamber 102.To provide for pressurizing in the chamber 102, alternate methods may beused. For example, the pipe 114 may communicate with a pipe 116 which inturn establishes communication with a manually operated blower 118. Avalve 120 may be provided in the pipe 116 to close or open samedepending on the use. In addition, a conventional valve connection 122may also communicate with pipe 114 to provide for a connection to a gaspressure source, such as carbon dioxide, should it be desired to fillthe chamber 102 with a non-explosive medium.

FIGURE 6 illustrates a slightly modified one-way drive connectionindicated generally at 124. In this embodiment, an angle bar 31identical with that previously described is attached to the rim 6.However, a flexible tab 128 is conventionally secured to the bag 100,such as by vulcanizing, and a pair of plates 130, 130 are arranged onopposed sides of the flexible tab 128, .and bolted thereto as at 132.The inner plate 130 has another angle 131 secured thereto in anyconventional manner, as by welding. The angle 131, of course, facesupwardly in opposition to the downwardly facing angle 31. The flmctionof the one-way drive connection is similar to that described in theearlier embodiment. However, the employment of the flexible tabarrangement 128 accommodates greater horizontal flexibility in theone-way drive connection 124 to aid in connection maintenance during allmovements of the roof.

From the standpoint of the centering force available during uncenteringroof action, it will be noted that in this embodiment provision is madefor variation in physical area contact between the tube seal and thetank shell on opposed sides of the roof. This is distinguished from theearlier embodiment wherein the multiple chambered seal arrangementprovided both area variation and pressure variation to aid in roofcentering.

Another feature illustrated in this embodiment, and one which may beapplied to the earlier embodiment, involves the incorporation of aflexible weather shield 136. The weather shield 136 comprises -a rigidplate having its opposed ends crimped, as at 137 and 138, to pro videfor rigidirty therein, and additionally to accommodate bolting to thetopflange 14 of the rim, as at 16. The weather shield 136 is, of course,peripherally arnanged around the entire roof, and extends outwardly fromthe rim 6 and upwardly therefrom to cover a major pontion of the spacebetween the rim 6 and the tank shell 2. The weather shield 136, ofcourse, deflects a major portion of any foreign matter, such as rain,snow or the like, onto the deck and prevents same from engaging the tubeseal and ultimately finding its way within the product storage volume.Additionally, the weather shield 136 is sufl'iciently flexible so thatshould any portion of it engage the tank shell during uncentering roofmovement, it will merely flex upwardly and return to its originalposition when the roof again becomes centered.

If desired, a roof centering wheel arrangement indicated generally at140 may also be employed. The arrangement 140 comprises a housing 142secured to the bottom of the roof 4. A shaft 144 protrudes from thehousing 142 and pivot-ally carries a wheel 146- on its outer endimmediately adjacent the tank shell 2. The shaft 144 is provided with acollar 148 which will be telescopically received within the housing 142,and which in turn engages a spring 150 disposed within the housing 142to normally bias the shaft 144 and carried wheel 146 outwardly towardthe tank shell. During severe uncentering roof action, the wheel 146will engage the tank shell 2, compressing the spring 150 and providingan additional force to return the roof to a substantially centralposition within the tank shell.

Thus, it will be seen that I have provided novel pressure tube sealarrangements which effectively seal the annular space between thefloating roof and a tank shell, and in addition provides a pressure tomaintain the roof centrally located in the tank. It will also be notedthat temperature rise of the surrounding atmosphere will heat the gas ineach tube section 10, causing an increased pressure therein whichincreases the effectiveness of the seal. If desired, the gas used ininflating tube sections 10 may be non-inflammable variety such as carbondioxide which would tend to reduce the possibility of possibleincidenceof fire hazard in the tank.

The invention as shown is by way of illustration and not limitation, andmay be subject to various modifications 7 without departing from thespirit thereof or the scope of the appended claims.

What is claimed is:

1. A floating roof gas seal arrangement comprising a cylindrical Itankshell; a roof arranged to float on liquid within the shell; said roofhaving anupstanding rim peripherally arranged thereon, said rim definingwith the shell an annular space around the entire roof; and seal meansto close said annular space comprising a flexible pressured tubedisposed throughout said annular space, first mounting means to connectan upper portion of the tube to the upper portion of the rim, a one-Waydrive connection attaching an intermediate portion of the rim to anintermediate portion of the tube adjacent the rim as seen in sideelevation view, said 'one-w-ay drive connection including a flexible tabattached to the tube, mounting means secured to the tab and spaced fromsaid tabbed attachment to the tube, an upwardly facing hook meansfixedly connected to said mounting means, and 'a continuous downwardlyfacing angle means secured to the rim for registering with said upwardlyfacing hook means.

2. In a sealing arrangement of the type including a floating roof havinga peripheral rim located on a liquid contained in a tank shell; a gassealing means carried solely by said floating roof so as to bepositioned between the upstanding roof rim and the tank shell formovement vertically along the tank shell, said gas sealing meanscomprising a flexible tube means made of a material having gasimpervious and wear resistant properties, a gas at relatively lowpressure disposed within said tube means maintaining it in an inflatedcondition, said tube means when inflated being dimensioned andconfigured so as to form a vertically elongated section disposed betweensaid roof rim and tank shell when the rim and shell are spaced normallyapart, and means including means supported from said roof rim connectedto vertically spaced apart sections of the inwardly related surface ofthe tube means for maintaining the tube means in its verticallyelongated sectional shape in sealing engagement with the roof rim duringvertical movement of the roof, said sections being spaced apart morethan 20% and less than 50% of the circumference of the crosssection ofthe tube means, said gas coaoting with said tube means to cause asubstantial portion of the inwardly related surface of the tube means tofrictionally engage at all times the roof rim, said gas and tube meanscoaoting to cause a substantial portion of the outwardly related surfaceof the tube means to engage the tank shell when the roof rim is normallyspaced from the tank shell and to cause a greater or lesser portion ofsaid outwardly related surface to engage the tank shell at all timeswhen the roof is less than or more than normally spaced from said tankshell.

3. In a sealing arrangement of the type including a floating roof havinga peripheral rim located on a liquid contained in a tank shell; a gassealing means carried solely by said floating roof so as to bepositioned between the upstanding roof rim and the tank shell formovement vertically along the tank shell, said gas sealing meanscomprising a flexible tube means made of a material having gasimpervious and wear resistant properties, a gas at relatively lowpressure disposed within said tube means maintaining it in an inflatedcondition and imparting substantial horizontal flexibility to said tubemeans for the purpose of maintaining an effective vapor seal betweensaid tank shell and tube means irrespective of spacing variationsbetween the roof rim and tank shell encountered during vertical movementof the roof, said tube means when inflated being dimensioned andconfigured so as to be resiliently disposed between said roof rim andtank shell during vertical movement of the roof irrespective of thespacing variations between the roof rim and tank shell, and meansincluding first and second spaced apart means connected to verticallyspaced apart sections of the inwardly related surface of the tube meansto maintain the tube means in its resilient position in sealingengagement with the roof rim during vertical movement of the roof, saidgas, tube means, and connecting means coacting to cause a substantialportion of the inwardly related surface of the tube means tofirictionally engage at all times the roof rim, said gas and tube meanscoaoting to cause a substantial portion of the outwardly related surfaceof the tube means to engage the tank shell when the roof rim is normallyspaced from the tank shell and to cause a greater or lesser portion ofsaid outwardly related surface to engage the tank shell at all timeswhen the roof is less than or more than normally spaced from said tankshell.

4. A floating roof gas sealing arrangement comprising a tank shell forcontaining liquid; a floating roof located on said liquid in said shelland including a peripheral upstanding rim; g-as sealing means positionedbetween the upstanding portion of the roof and the tank shell, said gassealing means comprising a flexible tube means carried by the upstandingrim of the roof, said tube means being made of a gas impervious and wearresistant material for containing a gas, a gas located within the tubemeans maintaining it in an expanded condition so that when the roof rimand the tank shell are normally spaced apart a substantial portion ofits outwardly related surface frictionally engages the tank shell and .asubstantial portion of its inwardly related surface at all timesfrictionally engages the rim of the roof, first mounting meansconnecting an upper section of the inwardly related surface of the tubemeans to the rim of the roof and operable to maintain the tube meansbetween the rim of the roof and the tank shell during upward movement ofthe roof, a second mounting means spaced vertically from said firstmounting means attaching another section of the inwardly related surfaceof the tube means to the rim of the roof and including an interlockingflange means on said roof rim and tube seal, the second mounting meansbeing operable to maintain the tube seal between the rim of the roof andthe tank shell during downward movement of the roof.

5. The sealing arrangement of claim 4 wherein the interlocking flangemeans comprises downwardly extending hook means suitably secured to therim of the roof and, further, an upwardly extending hook means suitablysecured to the tube means, the hook means being maintained in assembledinterlocking relation by the coaction of the tube means and the firstmounting means.

6. A floating roof gas sealing arrangement comprising a tank shellcontaining liquid; a floating roof located on said liquid and includinga peripheral upstanding rim; a gas sealing means carried solely by saidfloating roof so as to be positioned between the upstanding roof rim andthe tank shell for movement vertically along the tank shell, said gassealing means comprising a flexible .tube means made of a materialhaving gas impervious and wear resistant properties, a gas at relativelylow pressure disposed within said tube means maintaining it in aninflated condition, said tube means when inflated being dimensioned andconfigured so as to form a substantially vertically elongated sectionwhen disposed between the normally spaced roof rim and tank shell, andmeans including means supported from said roof rim connected tovertically spaced apart sections of the inwardly facing surfaces of thetube means, said last mentioned means tending to maintain the tube meansin its vertically elongated sectional shape during vertical movement ofthe roof in sealing engagement with both the roof rim and the tank shellirrespective of the relative distance between the roof rim and the tankshell, said sections being spaced apart more than 20% and less than 50%of the circumference of the cross-section of the tube means, said gascoaoting with said tube means to eflFect a horizontal flexibility of thetube means for accommodating variations in distance between the roof rimand the tank shell during vertical movement of the roof.

7. In a sealing arrangement of the type including a floating roof havinga peripheral rim located on a liquid contained in a tank shell; a gassealing means carried solely by said floating roof so as to bepositioned between the upstanding roof rim and the tank shell formovement vertically along the tank shell, said gas sealing meanscomprising a flexible tube means made of a material having gasimpervious and wear resistant properties, a gas at relatively lowpressure disposed within said tube means maintaining it in an inflatedcondition and imparting substantial horizontal flexibility to said tubemeans for the purpose of maintaining an effective vapor seal betweensaid tank shell and tube means irrespective of spacing variationsbetween the roof rim and tank shell encountered during vertical movementof the roof, said tube means when inflated being dimensioned andconfigured so as to be resiliently disposed between said roof rim andtank shell during vertical movement of the roof irrespective of thespacing veriati-ons between the roof rim and tank shell, and meansconnected to and supported by said roof rim and including first andsecond spaced apart means connected to vertically spaced apart sectionsof the in- Wardly related surface of the tube means to maintain the tubemeans in its resilient position in sealing engagement with the roof rimduring ventical movement of the roof, said gas, tube means, andconnecting means coacting to cause a substantial portion of the inwardlyrelated surface of the tube means to frictionally engage at all timesthe roof rim, said gas and tube means coacting to cause a substantialportion of the outwardly related surface of the tube means to engage thetank shell when the roof rim is normally spaced from the tank shell andto cause a greater or lesser portion of said outwardly related surfaceto engage the tank shell at all times when the roof is less than or morethan normally spaced from said tank shell.

References Cited in the file of this patent UNITED STATES PATENTS1,674,038 Glass June 19, 1928 1,854,535 Wiggins Apr. 19, 1932 1,986,869Welp Jan. 8, 1935 2,085,752 Horton et al. July 6, 1937 2,538,875 LairdJan. 23, 1951 2,651,433 Mjellem Sept. 8, 1953 2,968,420 Harris et a1Jan. 17, 1961

1. A FLOATING ROOF GAS SEAL ARRANGEMENT COMPRISING A CYLINDRICAL TANKSHELL; A ROOF ARRANGED TO FLOAT ON LIQUID WITHIN THE SHELL; SAID ROOFHAVING AN UPSTANDING RIM PERIPHERALLY ARRANGED THEREON, SAID RIMDEFINING WITH THE SHELL AN ANNULAR SPACE AROUND THE ENTIRE ROOF; ANDSEAL MEANS TO CLOSE SAID ANNULAR SPACE COMPRISING A FLEXIBLE PRESSUREDTUBE DISPOSED THROUGHOUT SAID ANNULAR SPACE, FIRST MOUNTING MEANS TOCONNECT AN UPPER PORTION OF THE TUBE TO THE UPPER PORTION OF THE RIM, AONE-WAY DRIVE CONNECTION ATTACHING AN INTERMEDIATE PORTION OF THE RIM TOAN INTERMEDIATE PORTION OF THE TUBE ADJACENT THE RIM AS SEEN IN SIDEELEVATION VIEW, SAID ONE-WAY DRIVE CONNECTION INCLUDING A FLEXIBLE TABATTACHED TO THE TUBE, MOUNTING MEANS SECURED TO THE TAB AND SPACED FROMSAID TABBED ATTACHMENT TO THE TUBE, AN UPWARDLY FACING HOOK MEANSFIXEDLY CONNECTED TO SAID MOUNTING MEANS, AND A CONTINUOUS DOWNWARDLYFACING ANGLE MEANS SECURED TO THE RIM FOR REGISTERING WITH SAID UPWARDLYFACING HOOK MEANS.